Everything you need to know about iPhone OS 4.0


The iPhone OS 4.0 event just wrapped up and the faithful are filing out of the Apple venue with a slightly shell-shocked look. What happened? Oh nothing, just multi-tasking, iAd, a huge Mail update and a bunch of other stuff. Yes, the long-awaited OS update for the iPhone has just been run down and we’ve got all the details.

Here, in handy bullet point form, are all the things you need to know about iPhone OS 4.0…


  • There have been 50 million iPhones sold so far (along with 450,000 iPads)
  • OS 4.0 will be going out to phones this summer, but a developer preview is currently available. The iPad will get it in the fall. iPhone and iPod touch 1Gs are out of luck, I’m afraid.
  • Thousands of new APIs, including many “accelerate” APIs which allow developers to add hardware acceleration
  • Multi-tasking is coming. They admit they are a bit late to the party. Video here, details below.
    -double tap of home button shows running applications. Invoke at any time, it’ll pause games and so on.
    -the app-switching tray pushes up the other home icons and has a sort of metallic background.
    -it’s a bit disappointing, actually: it’s more the ability to switch quickly between “active” apps. Nice, though.
    -it’s not a task manager. You can’t close or modify apps, and Jobs says you don’t need to. Furthermore he says that if the user needs a task manager, the UX team is blowing it.
    iPhone 3G and iPod touch 2nd gen will not get multitasking.
  • There are seven background services that will be allowed, and which shouldn’t significantly affect the performance of other apps:
    Background audio: i.e. Pandora can play in the background and popup controls can control it.
    Background VoIP: Skype calls will continue if you need to switch apps; a “return to call” button will show, and you can also receive Skype calls on a locked phone.
    Background location: turn-by-turn directions can continue when you leave the app. Music can run at the same time and will quiet down when directions need to be said. Very slick. Uses cell-tower-enhanced AGPS. A notification will show in the status bar if an app is transmitting your location. You can also turn off location app-by-app.
    Push notifications: the same push notifications you know and love.
    Local notifications: in-phone notifications for, say, pop-up alarms and such. Local app stuff.
    Fast app switching: this is the service by which apps can store their state when you switch to and from them.
    Task completion: allows, say, a Flickr upload to continue if you close the app.
  • Folders. These are basically stacks of apps. Drag one app onto another to create a folder. This will really help un-clutter some iPhone screens (makes room for people to buy more apps). Makes for a maximum of 2160 apps. Is there an app for taking it easy on app downloading?
  • Homescreen wallpapers. Yes, very nice.
  • Enhanced mail. Several changes here:
    Unified inbox. Web mail, MobileMe, multiple exchange accounts – thank god. This is nice.
    Thread organization. Handy for such a powerful inbox.
    Attachments for third-party email. Get your Gmail attachments right in Mail now.
  • iBooks: I think we all expected this. It looks just like the iPad version, though somewhat smaller, obviously. Sync bookmarks and such between devices. Comes with Winnie the Pooh!
  • Better email encryption, and some sort of in-app encryption is in the works.
  • SSL VPN support. Non-bold flavor text.
  • Social gaming features: challenge friends to games, compare high scores on leaderboards and so on. Matchmaking and achievements. Nice, looking forward to this on the iPad. Hot seat Civ 4 with someone I’ve never met? Why not?
  • Support for Bluetooth keyboards
  • May support camera with flash (not confirmed)
  • iAd: In Steve’s words, somewhat paraphrased: “Developers [of free apps] need to find a way to start making their money. A lot of developers turn to advertising – and we think these current advertisements really suck. If you look at advertisements on a phone, it’s not like on a desktop. On a desktop, its about search. On mobile, search hasnt happened. People aren’t searching on their phones. People are spending their time in apps. The average user spends over 30 minutes using apps on their phone. If we said we wanted to put an ad up every 3 minutes, that’d be 10 ads per device per day — about the same as a TV show. We’re going to soon have 100m devices. That’s a billion ad opportunities per day! “This is a pretty serious opportunity, and it’s an incredible demographic. But we want to do more than that. We want to change the quality of the advertising. We’re all familiar with interactive ads on the web. They’re interactive, but they’re not capable of delivering emotion. We have figured out how to do interactive and video content without ever taking you out of the app.”
    Apple will sell and host the ads; the revenue will be split 60/40, with devs getting the 60. Anybody can make them, just like apps.
    Ads are done in HTML5 (a little dig in there for Adobe)
    Fully interactive; the Toy Story ad he showed looks like a native app, includes a game, graphical interface and everything. They can call out for showing times, current prices, and so on. It’s essentially a commercial break app.
    Access to APIs: somewhat scarily, ads will have access to location, accelerometer, and a lot of other stuff.


That’s all! Pretty crazy update, actually. We’ll be filling out coverage throughout the day with more careful examinations of the new features. You can also check out Apple’s official 4.0 page if you like, or watch the keynote.